Started `Module` module.
Type refactoring. Created vector_t and pointer_t.
lltype function calls shoud not need coercion anymore.
Removed integer vector comparison function, which has been included into
the regular integer comparison function (as it is in LLVM IR).
Indentation and wording.
Unsafe aggregate type implemented (arrays and structures).
{extract,insert}value instructions added (also unsafe).
Merge branch 'module'
Fixed data_layout and target_triple functions.
Instruction makers usage rules added in comments,
Doc++.
Fixed br signature (condition is now [`I1]).
Rebasing branch 'untyped' on '3d15114'.
(No static type checking, array and structure operations implemented).